Checkbook calculator



FIG. 1 is a front, left, bottom perspective view of a checkbook calculator, showing my new design;

FIG. 2 is a front elevation view thereof shown in its open position;

FIG. 3 is a rear elevation view thereof shown in its open position;

FIG. 4 is a left side view thereof shown in its open position;

FIG. 5 is a right side view thereof shown in its open position;

FIG. 6 is a top view thereof shown in its open position; and,

FIG. 7 is a bottom view thereof shown in its open position.

FIGS. 2-7 are drawn on a reduced scale from FIG. 1. 

The ornamental design for a checkbook calculator, as shown and described. 